Fibronectin binding domain chimeric antigen receptors and methods of use thereof

Abstract

Provided herein are chimeric antigen receptors (CARs) for binding with a target antigen, comprising at least one antigen specific targeting region comprising a fibronectin type 3 (FN3) domain polypeptide. Provided herein are multispecific chimeric antigen receptors for binding with two or more target antigens, comprising at least two antigen specific targeting regions comprising a fibronectin type 3 domain polypeptide. Also provided herein are compositions and methods of treatment relating to the use of subject CARs of the invention.

What is claimed is: 
     
       1. A chimeric antigen receptor (CAR) comprising:
 i) at least one antigen specific targeting region comprising a fibronectin type 3 (FN3) domain polypeptide; 
 ii) a transmembrane domain; and 
 iii) an intracellular signaling domain, 
 wherein the CAR further comprises an extracellular spacer domain 
 wherein the least one antigen specific targeting region comprises an amino acid sequence set forth in SEQ ID NO: 33. 
 
     
     
       2. The chimeric antigen receptor of  claim 1 , wherein the extracellular spacer domain is selected from the group consisting of an Fc fragment of an antibody, a hinge region of an antibody, a CH2 region of an antibody, a CH3 region of an antibody, an artificial spacer sequence, a hinge consisting of an amino acid sequence of CD8, and any combination thereof. 
     
     
       3. The chimeric antigen receptor of  claim 1 , wherein the chimeric antigen receptor further comprises at least one co-stimulatory domain. 
     
     
       4. The chimeric antigen receptor of  claim 1 , wherein the transmembrane domain is selected from the group consisting of an artificial hydrophobic sequence and transmembrane domains of a type I transmembrane protein, an alpha, beta, or zeta chain of a T cell receptor, a cluster of differentiation 28 (CD28), a CD3 epsilon, a CD45, a CD4, a CD5, a CD8, a CD9, a CD16, a CD22, a CD33, a CD37, a CD64, a CD80, a CD86, a CD134, a CD137, and a CD154. 
     
     
       5. The chimeric antigen receptor of  claim 1 , wherein the intracellular signaling domain is selected from the group consisting of cytoplasmic signaling domains of a human CD3 zeta chain, a FcyRIII, a FcsRI, a cytoplasmic tail of an Fc receptor, an immunoreceptor tyrosine-based activation motif (ITAM) bearing cytoplasmic receptors, a TCR zeta, a FcR gamma, a FcR beta, a CD3 gamma, a CD3 delta, a CD3 epsilon, a CD5, a CD22, a CD79a, a CD79b, and a CD66d.